Apparatus for saturating fabrics



Feb. 22, 1949. A v I F, w, DAMS' 2,462,297

APPARATUS FOR SATURATING FABRICS Filed April 9, 1945 A I 2 Sheets-Sheet 1 N "L I w N N k INVENTOR.

FlaydWAdams Arm/wry Feb. 22, w. ADAMS APPARATUS FOR SATURATING FABRICS 2 Sheets-Sheet 2 ll llllllllllllll-l'ulll'lllvllllnllllllllll llllalllllllll-llllllllnlllvlll-l'liluullllllllvl Filed April 9. 1945 Patented Feb. 22, 1949 UNITED STATES PATENT OFFICE APPARATUS FOR SATURATING FABRICS Floyd W. Adams, Los Angeles, Calif., assignor to Los Angeles Paper Box'Factory, Los Angeles, Calif., a corporationof California Application April 9, 1945, Serial No. 587,253

Claims.

' felt in a bath of hot saturant, such as asphalt.

Several immersions were necessary to obtain desired impregnation. This conventional method had several faults. It entailed the use of an unduly large amount of saturant; the heat loss in the method was excesively great and, therefore, uneconomlcal; it was difficult to thread and pass the fabric through the bath; a break in the fabric entailed a considerable loss of yardage thereof; the immersion time for full saturation was unduly long; and because of the latter, the excessive heat tended to char the fibres of the fabric, and, consequently, to weaken the fabric.

Further, all dry felts contain some moisture and in the immersion method of saturating, this moisture is carried into the bath. Since any appreciable amount of such moisture will cause violent foaming when introduced in hot asphalt,

the bath will frequently foam over and entail a shut-down to clean up the resultant mess. Again, the great difference in the temperatures of the felt sheet and the hot asphalt in the immersion bath will cause the asphalt to chill upon contact with the sheet and to form an impervious film thereon. It follows then, that before impregnation can occur,'this film must be dissipated entailing another wasteful use of time.

Another prior method of saturating felt sheets with asphalt entailed spraying hot asphaltupon one surface of the sheet in an attempt to drive the moisture in said sheet outthrough the other surface. While the spraying method affords increased efliciency over the immersion method, it is time consuming, costly, and only partly solves the problems involved. Control of impregnation is difficult and an uneven product results.

When saturating flocculent fabrics, the greater proportion of saturant fills the spaces or interstices of the fabric fibres. Therefore, a fabric which is initially filled with saturant, upon cooling, may be considerably undersaturated. This is caused by the great difference in the expansion co-efllcients of asphalt and the like and fabrics. The present invention, therefore, contemplates a method for impregnating fabrics in which the above-mentioned faults are obviated and by means of which a fabric'can be saturated fully and unifnrmlv thrnu nmii. its thickness.

2 Other objects of the invention are to provide a method for saturating fabrics in which the moisture in the fabric is driven therefrom without foaming and to provide a method in which the impregnation is controlled to produce a uniform product having a desired degree of saturation.

A further object of the invention is to provide a fabric saturation method in which surface filming is obviated by preventing the formation ofv a cooled crust of asphalton the material.

A further object of the invention is to provide novel apparatus for carrying out the herein contemplated method for saturating fabrics.

My invention also has for its objects to provide such means that are positive in operation, convenient in use, easily installed in a working position and easily disconnected therefrom,

the present invention, which is given by way of llustration or example only.

In the drawings, like reference characters designate similar parts in the several views.

Fig. 1 is a cross-sectional view, in somewhat diagrammatic form. of preferred apparatus for carrying out the method of the invention.

Fig. 2 is a plan-sectional view as taken on the plane of line 2-2 of Fig. 1.

Fig. 3 is a cross-sectional view as taken on theline 33 of Fig. 1 and drawn to an enlarged scale.

The apparatus of the present embodiment for carrying out the method of the invention may comprise essentially: heated saturating means A; means B for conveying a fabric for impreg-' nation by the saturating means A; fabric dipping means C; means D for controlling the degree of saturationof the fabric after leaving the means C; and various other parts, details and structural features.

The saturating means A may comprise a plurality of saturating platens. In this case, two such platens l0 and II are provided. Each .platen may comprise a cast iron or steel plate or block of suitable size and proportion. Means may be provided to heat the platens. The heating medium may be superheated steam or the like. When asphalt is the saturant to be used in the method, it is desired to heat the platens to a temperature of about 500 F. I have found that a preferred heating medium is a vapor known as Dowtherm Vapor," since this vapor boils at 500 F. at atmospheric pressure and at 650 F. at a pressure of 29 pounds. Dowtherm is an eutectic mixture of the following organic compounds: diphenyl, 26 and diphenyloxidep 73 /2%. This compound has a low boiling point but has high latent heat and the vapor thereof is particularly suited as a heating medium in the present apparatus. No matter what type of heating medium which I may use, I provide a plurality of cored through holes i2 arranged adjacent to the respective upper and lower surfaces l3 and ll of said platens. It is evident that a heating medium circulating through the platens in the holes l2 will heat the surfaces l3 and I4 thereof as desired.

Each platen, the platen ill at its upper and lower surfaces, and the plate H at its upper surface only, is provided with one or more saturant.fiow means such as the channels i5. I preferably form each channel as a transverse cored hole l6 and with a relatively narrow slot il connecting said cored hole and adjacent surface portions of the platen. I provide inlet and outlet pipe connections i8 and an outer inter-connection IQ for the various channels l whereby saturant, from a suitably heated storage source, may be circulated through said channels in an obvious manner. The connections 18 and i9 may be jacketed or otherwise insulated to minimize heat loss. By means of this heated platen, the fabric is heated to approximately the temperature of the saturant. Moreover, since the saturant is very fluent because of its high temperature, it quickly and thoroughly penetrates the substantially as hot fabric without encrusting the fabric.

The means B may comprise a perforate, endless belt conveyor 20, such as woven wire mesh, which is arranged on rollers 2|, 22, 23 and 24. I may drive any or all said rollers, but prefer that rollers 2i and 22 be driven, the rollers 23 and 24 being idlers. The belt is trained to engage the'top and bottom surfaces l3 and ll of the platen I0, and the top surface ill of the platen II as best seen'in Fig. 1. By this arrangement, a fabric sheet F, of the nature herein set forth, may be introduced between the belt conveyor and the heated surface ill of platen ill to be moved by said conveyor in intimate contact with said surface and the other heated surfaces of the platens.

As the fabric sheet passes over the slot ll of the first channel i5 which it encounters, it picks up saturant from said slot. The amount of saturant which it picks up will depend on the pressure on the saturant as supplied by the mentioned storing means. After passing the first slot, the sheet thus at least partially impregnated, maintains close sliding contact with the heated surface 13 of the platen. Since the temperature of the platen is maintained at or above the temperature of the saturant, plasticity of the saturant in the fabric is retained to obviate chilling thereof. In other words the saturant in the fabric is prevented by the heated platen from cooling off sufficiently to form a crust thereon. Further, the movement of the fabric, under pressure of thebonveyor belt, across the surface of the platenyirons the saturant into the fabric.

By the time the fabric passes over the next succeeding slot I1, the saturant previously picked up is ironed into the fabric. This process continues until the fabric leaves the discharge end of the platen. Ii. By that time, there is substantially uniform application of the saturant through the fabric.

Since .the saturant is picked up by one side only of the fabric, any moisture is free to escape from the other side thereof and through the perforations of the belt 20, and at no time comes into contact with the saturant. The previously mentioned faulty foaming is, therefore, prevented. The rate of saturation can be controlled by the speed of movement imparted to the conveyor and can be reasonably high since all affected parts are kept at a desired high heat. Since the saturant and fabric are both maintained hot and the saturant is maintained in a liquid state at all times, penetration into the fabric is rapid.

I further provide the dipping means C through which the fabric, as impregnated by the means A, passes for final saturation. For this purpose, I provide a dip tank 30 for a quantity of saturant, and heat said saturant as by means of pipes 3! through which circulate the heating medium hereinbefore described. The dip tank may be provided with a roller 32 under which the fabric is trained to pass out through the open top of the tank. In order to facilitate threading the fabric around the roller 32 I provide means for.

raising said roller out of the saturant in which it is immersed. Such means may comprise a gear rack 33 vertically disposed at eachend of the tank and having the shaft 34 of said roller 32 journaled therein: a pair of gear pinions ll, meshing with the respective racks and carried by a common shaft 38; and a handle 31 for rotating the shaft 36 to cause vertical movement of the racks, and, consequently, vertical movement of the roller 32. Accordingly, either direction of rotation of the handle, will cause respective raising and lowering of the roller 32.

As the fabric leaves the dip tank 30, a large amount of saturant will cling to both of its surfaces and much of this will flow back into the tank. However, since it is desired to control the thicknessof the saturant on said fabric surfaces, the means D is provided. For this purpose, I provide vibrating means 40 and H arranged on either side of the fabric so that said fabric passes between them. Each means 40 and ll may comprise a doctor blade 42 pivoted as at ll, and connected to means 44 for vibrating the blade. Any suitable type of vibrating means may be used; one such means may comprise an electric vibrator, known as the "Syntron type. I only desire that the vibrating means be of a type capable of adjustment to vary the degree and intensity of vibration.

If the doctor blades are maintained stationary and tightly against the fabric as it passes between said blades, practically all of the saturant which the fabric picks up from the dip tank will be scraped off, leaving little or no surface saturation on the fabric sheet. If the doctor blades are slightly vibrated, a relatively thin surface saturant film will be left and the remainder scraped off. It is evident that the greater the length of throw or reciprocating movement of the doctor blades, the thicker will be the surface films upon the fabric. The films left on the surfaces of the fabric by the vibrating blades is sucked into the interstices of the fabric. upon cooling, because of the considerably larger amount of contraction of the saturant than the fabric, upon cooling. The purpose of this surface saturation, by dipping, is to leave on the surface ofthe fabric sufficient saturant to thoroughly and uniformly impregnate the fabric, when the saturant cools.

. In the present specification, including the hereunto appended claims, the word fabric" shall be taken to have a broad meaning, to wit, to

include woven, knit, felted, or matted material.

While I have illustrated and described what I now regard as the preferred embodiment of my invention, the construction is, of course, subject to modifications without departing from the spirit and scope of my invention. I, therefore, do not wish 'to restrict myself to the particular form of construction illustrated and described, but desire to avail myself of all modifications that may fall within the scope of the appended claims, which are designed for the purpose of carrying out the method herein set forth and such or near variations thereof.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. Apparatus for impregnating absorbent sheets, comprising ironing platen means having a plurality of saturant circulating channelsbelow the surface thereof, said channels having throats I opening and terminating at the surface, and

means for moving one side of an absorbent sheet in surface engagement with the platen means to pick up saturant from the throats, said platen of the sheet, said platen having transverse passageways for heating mediums. said passageways surface, said passageways throats.

4. Apparatus for impregnating absorbent sheets, comprising ironing platen means having a plurality of saturant circulating channels opening at the surface thereof, and means for moving an absorbent sheet in surface engagement with the platen means to alternately pick up saturant from openings in the channels and iron said saturant into the interstices of the sheet, said piaten means including a plurality of the transverse passageways connected to a source to heat at least one surface of said platen means between and in spaced relation to said channel openings, said latter means comprising an endless perforated conveyor belt.

5. In an apparatus of the character referred to. a body having a substantially planar surface having transverse provided with spaced transverse throats and with channels near the surface communicating with said throats, said channels being connected to be supplied with a saturant for an absorbent sheet of paper, said planar surface formin between 'said throats, an ironing area, and said body probeing arranged in alternate relation to said channels.

3. In apparatus of the character described, a platen having transverse passageways for circulating a heating medium in said platen to heat at least one surface thereof, and means dividing said platen surface into alternate fluid circulating channels and ironing areas, said means comprising transverse passageways connected with 55 a source of fluid supply and disposed near said vided near the planar surface thereof with transverse passageways for a heating medium, and means to pass one side of a sheet of material over said planar area'and the throats to wipe the saturant upon said side of thesheet and immediately to iron the saturated area.

FLOYD W. ADAMS.

REFERENCES CITED The following references are of record in the flle of this patent:

. UNITED STATES PATEN'IB Number Name Date 346,869 Sherck et al. Aug. 3, 1886 453,090 Newman May 26. 1891 667,041 somerville Jan. 29, 1901 1,347,095 Harrison May 20, 1920 1,385,042 Decker et a1 July 19, 1921 1,736,633 Schutte Nov. 19, 1929 1,776,590 Kirschbraun Sept. 23, 1930 1,866,689 Wilshire July 12, 1932 2,058,369 Taylor Oct. 20, 1936 2,065,576 George Dec. 29, 1936 2,063,253 Williams Jan. 19. 1937 2,115,630 Gruber-Rehenburg Apr. 26, 1933 2,159,152 Hershberger May 23, 1939 2,206,056 Sheesley July 2. 1940 2,313,108 Wertz Mar. 9, 1943 2,347,555 Greene Apr. 25, 1944 2,385,916

Hahn Oct. 2, 1945 

